5. History, tradition and abundant ecclesiastical institutions bear outstanding witness to the great merit owing to the Eastern Churches by the universal Church.5 The Sacred Council, therefore, not only accords to this ecclesiastical and spiritual heritage the high regard which is its due and rightful praise, but also unhesitatingly looks on it as the heritage of the universal Church. For this reason it solemnly declares that the Churches of the East, as much as those of the West, have a full right and are in duty bound to rule themselves, each in accordance with its own established disciplines, since all these are praiseworthy by reason of their venerable antiquity, more harmonious with the character of their faithful and more suited to the promotion of the good of souls.

6. All members of the Eastern Rite should know and be convinced that they can and should always preserve their legitimate liturgical rite and their established way of life, and that these may not be altered except to obtain for themselves an organic improvement. All these, then, must be observed by the members of the Eastern rites themselves. Besides, they should attain to on ever greater knowledge and a more exact use of them, and, if in their regard they have fallen short owing to contingencies of times and persons, they should take steps to return to their ancestral traditions.

Those who, by reason of their office or apostolic ministries, are in frequent communication with the Eastern Churches or their faithful should be instructed according as their office demands in the knowledge and veneration of the rites, discipline, doctrine, history and character of the members of the Eastern rites.6 To enhance the efficacy of their apostolate, Religious and associations of the Latin Rite working in Eastern countries or among Eastern faithful are earnestly counseled to found houses or even provinces of the Eastern rite, as far as this can be done.⁷